Wednesday, August 17, 2011

Crayfish, also called crawfish or crawdad, are closely related to the lobster. More than half of the more than 500 species occur in North America, particularly Kentucky (Mammoth Cave) and Louisiana in the Mississippi basin. Crayfish also live in Europe, New Zealand, East Asia and throughout the world, including the Tristan da Cunha Islands. Nearly all live in freshwater, although a few survive in salt water. Crayfish are characterised by a joined head and thorax, or midsection, and a segmented body, which is sandy yellow, green, or dark brown in colour. The head has a sharp snout, and the eyes are on movable stalks. Crayfish are usually about 7.5 cm (3 inches) long.

In the open circulatory system blood flows from the heart through the arteries and returns into open sinuses. The digestive system has a stomach for grinding food and a gland for chemical processing. The antennal gland is the main excretory organ.

Saturday, August 6, 2011

Crabs have one set of claws and four other pairs of legs. If a predator grabs a leg of a crab, the crab will shed it and later it will grow back.

Lined Shore crabs dance sideways down to the sea. They scrape small plants off rocks with the tiny cups on their pincers. The Lined Shore crab hides in the cracks of rocks.

Hermit crabs make their homes in empty snail shells. The hermit crab's back legs hold its shell on tight. The borrowed shells protect their soft bodies. As a hermit crab grows, it needs a bigger shell. Some hermit crabs will try and steal another's shell. They are scavengers who look for dead plants and animals that have fallen to the bottom of the tide pool.

The male crab shoots sperm into two hollows between the females back legs. That will make it possible for the female to lay eggs. When the eggs hatch, they are called zoea larva. The zoea larva feed in the ocean by trapping its food in its bristles. After a while the zoea larva change shape and are called megalopa larva. When the megalopa gets too heavy, it sinks to the bottom of the sea and starts to live as a crab. As the baby crab starts growing, it has to hide because its shell is soft. As it grows, its shell gets harder. Then when the crab gets too big for its shell, the shell cracks and falls off. This is called molting.

Diet

Some crabs are scavengers and eat dead animals. Some eat plankton. Some young crabs eat worms. Larger crabs eat shrimp and other shellfish.

Size

From 1 centimeter to nearly 2 meters

Color

Lined Shore crab - reddish-purple

Kelp crab- brown on top, reddish below

Purple Shore crab - dark purple with purple spots on claws

Hermit crab - gray-green

Lumpy crab - red-brown

Rock crab - light purplish-red

Life Cycle

Crab eggs hatch into zoea larva which turn into megalopa larva and then into crabs.

Predators

fish, birds, octopus, and sea otters

Neat Facts

A barnacle sometimes gets inside a male crab and takes nourishment from its blood and changes its sex hormones, so the next time it loses its shell it is a female.

Frogs have very good eyesight. They bulge out the sides of their heads in order for the frog to see in nearly all directions. Frogs also have amazing sense of hearing. You can often tell the difference between a male and female frog by the size of their eardrum, which can be seen behind their eyes. If the eardrum is smaller than the eye, the frog is a female. On males their eardrum is the same size as the eye.

Frogs have very powerful back legs and webbed feet that help them jump great distances, as well as, swim. Frogs even use their legs to dig, or burrow, underground forhibernating. Certain frogs can jump up to 20 times their own body length in a single leap. Every different species of frog has his or her own look. They come in many colors, patterns and sizes.

Frogs have many predators. Animal predators include birds, fish and reptiles.Most rainforest frogs have pads of sticky hairs on their fingers and toes, as well as, loose sticky skin on their bellies, that make them great climbers to escape their predators. Many of these frogs live in high trees for safety.Other frogs are very good at camouflaging themselves so that they blend in with their environment, making it harder for their enemies to find them. A frog can change the colour of its skin depending on its surroundings.

FROGS vs. TOADS

Many people don’t know the difference between frogs and toads. They are quite different animals, although they belong to the same animal group.

Frogs:

Need to live near water

Have smooth, moist skin that makes them look “slimy”.

Have a narrow body

Have higher, rounder, bulgier eyes

Have longer hind legs

Take long high jumps

Have many predators

Toads:

Do not need to live near water to survive

Have rough, dry, bumpy skin

Have a wider body

Have lower, football shaped eyes

Have shorter, less powerful hind legs

Will run or take small hops rather than jump

Do not have many predators. Toad’s skin lets out a bitter taste and smell that burns the eyes and nostrils of its predators, much like a skunk does.

Wednesday, August 3, 2011

* In Nigeria 81% of its original forest cover is now permanently lost.

*The tropical rainforests of Brazil lost 90-95% of their trees over the decade.

*The forests of Central America are down by Two-thirds low lands,since 1950.

*Countries like India,Mexico,Philiphines,China,Indonesia,Sri Lanka,Thailand and the Congo lost 50% of their rainforests.

:: effect of deforestation ::

*Loss of fuel wood,means depriving soil of nutrition , leads to a receding forest.It causes an increase in rainfall , risks of flooding and soil erosion.

*A loss of trees emits a high concentration of carbon dioxide and other greenhouse gases , which cause green house effect and increase global temperature slowly.

*It also leads to drier atmosphere that increases the risk of forest fires.

*The watershed protection of the forests diminishes , leading to stream erosion ,loss of fisheries and water supply , as well as the loss of reaction.

what do you think the use of technology in reducing and minimizing the problem?

In think,the use of technology in reducing and minimizing the problem is we can use media electronic like make the advertisement about minimizing the deforestation.

In your opinion ,blog is able to stimulate environmental awareness among

community.elaborate.

In my opinion,blog is able to stimulate environmental awareness among community especially the blogger because the blogger always like to share their information on blog because they have many their blog followers.So,base on the topic about awareness of deforestation,they can get or share many ideas about it.